Unit Size Calculator
Translate your bankroll and risk tolerance into a concrete dollar "unit" - the standard bet size handicappers reference when they call a play a "1-unit" or "3-unit" bet.
Bankroll & Risk
Your Unit Sizes
Risk Profile Comparison
Unit Size Calculator
Sports bettors and handicappers commonly describe the size of a bet in "units" rather than dollars (e.g. a "3-unit lock"). This calculator converts your bankroll and chosen risk profile into the dollar value of a single unit, plus a quick table of common unit multiples.
Why Use Units Instead of Fixed Dollar Amounts?
- Bankroll-relative: as your bankroll grows or shrinks, your unit size scales automatically instead of staying fixed.
- Comparable across bettors: a "2-unit play" means the same relative risk whether the bettor has $500 or $50,000, which is why touts and handicappers publish picks in units rather than dollars.
- Discipline: capping your standard bet at a small percentage of bankroll (typically 1-3%) is one of the simplest ways to survive a losing streak without going broke.
Formulas
1 Unit = Bankroll * (Unit % / 100)
Unit Table = 1 Unit * [0.5, 1, 1.5, 2, 2.5, 3, 4, 5]
Typical Risk Profiles
| Profile | Unit % of Bankroll |
|---|---|
| Conservative | 1% |
| Moderate | 2% |
| Aggressive | 3% |
| Very Aggressive | 5% |
Most long-term profitable bettors stay at the conservative-to-moderate end; unit sizes above 5% expose the bankroll to steep drawdowns even with a real edge.
Kelly Criterion Cross-Check
If you have an estimate of your true win probability and the odds you're betting at, the calculator can cross-check your chosen unit % against the Kelly Criterion, which gives the mathematically edge-optimal bet size:
Decimal Odds = odds > 0 ? odds/100 + 1 : 100/|odds| + 1
b = Decimal Odds - 1
p = Win Probability
q = 1 - p
Full Kelly % = (b*p - q) / b
Quarter Kelly % = Full Kelly % / 4
Breakeven Win Rate = 1 / Decimal Odds
Flat unit sizing and Kelly sizing answer different questions: flat units are about risk tolerance and bankroll survival, while Kelly is about long-run growth given a specific edge. Many bettors use flat units for most bets and reserve larger, Kelly-informed sizing for spots where they have strong conviction in their edge. If your flat unit % is larger than even full Kelly, that's a signal you may be over-betting relative to your actual edge.
Practical Notes
- Recalculate your unit size periodically as your bankroll changes - a unit should always be a percentage of current bankroll, not a number you fix once and never revisit.
- Separate "bankroll" from money you need for other purposes. Only wager with money allocated specifically for betting.
- A losing streak of 10 units at 2%/unit costs about 20% of a bankroll (assuming flat sizing) - use the Risk of Ruin Calculator and Drawdown Calculator alongside this tool to understand how a given unit size holds up over a long series of bets.